Figure 2.

Flow profiles for metabolism, transport and deposition of ABA in control maize (Zea mays L.) plants and those inoculated with V. paradoxus 5C-2 over 8 d of the study period starting 6 d after planting. After treatment with V. paradoxus, the surface of the maize roots appeared slightly yellow, indicative of successful bacterial colonisation (V. paradoxus has characteristic yellow colonies in vitro). Based on the assumption that mass flow occurs both in xylem and phloem, the net K flows (obtained as described in¹⁶ and the ratios of ABA:K in the transport fluids were used to estimate the net flows of ABA in the two transport pathways over the study period. The increments of ABA in the maize tissues were calculated from two harvests (6 d and 14 d after planting). The metabolism of ABA in maize tissue was calculated according to.¹⁷ Dotted arrows indicate flows in the phloem, black arrows flows in the xylem. The width of the arrows (flows), the areas of the squares (deposition), and of the circles (complete circles, net synthesis; dotted circles, net degradation) are drawn in relation to the rates of flows. The numbers beneath the arrows, squares and circles indicate the net flows in nmol plant^-1 8 d^-1. Further details will be reported elsewhere (Jiang et al. manuscript in preparation).